Apparatus for shingling flat sheets

ABSTRACT

A vertical stack of flat sheets such as paperboard blanks is fed horizontally against an inclined support converging in the direction of movement of the stack. Said support is part of a Vshaped shingling conveyor mounted for pivotable movement from a receiving position to a discharge position. At the discharge position of the shingling conveyor, the sheets are shingled by a plurality of conveyors moving at progressively increasing speeds and then transferred to an outfeed conveyor associated with and controlled by the hopper of a vacuum feed table.

United States Patent 1 [ll] 3,885,781 Krebs May 27, 1975 [54] APPARATUSFOR SHINGLING FLAT 3,643,939 2/1972 Nussbaum 27l/DlG. 7

SHEETS 3,705,719 12/1972 Polit et a1. 2711010. 7

Charles H. Krebs, Lindenwold, NJ.

Molins Machine Company, Inc., Camden, NJ.

Filed: June 13, 1973 Appl. No.: 369,634

Inventor:

Assignee:

[1.8. CI 27l/3.l; 271/151 Int. Cl B65h l/30 Field of Search 271/DIG. 7,4, 7, 10, 34, 271/37, 105, 132,136, 151, 3.1, 258, 264, 272; 214/6 C, 6D, 8.5 B

References Cited UNITED STATES PATENTS Hartman 271/DIG. 7 Nelson etal.... 198/125 X Miller et al. 27l/DIG. 7 Huntwork 271/45 PrimaryExaminer-Evon C. Blunk Assistant Examiner-Bruce H. Stoner, Jr. Attorney,Agent, or FirmSeidel, Gonda & Goldhammer [57] ABSTRACT A vertical stackof flat sheets such as paperboard blanks is fed horizontally against aninclined support converging in the direction of movement of the stack.Said support is part of a V-shaped shingling conveyor mounted forpivotable movement from a receiving position to a discharge position. Atthe discharge position of the shingling conveyor, the sheets areshingled by a plurality of conveyors moving at progressively increasingspeeds and then transferred to an outfeed conveyor associated with andcontrolled by the hopper of a vacuum feed table.

13 Claims, 13 Drawing Figures PATENTEU W27 7 SHEET APPARATUS FORSHINGLING FLAT SHEETS The present invention is directed to apparatus forinverting, shingling, and feeding flat sheets such as paperboard blanks.The paperboard blanks are of a type adapted to be fed one at a time by afeed table to a converting machine such as a printer-slotter, afoldergluer, a folder-taper, die cutter, etc. The feed table includes ahopper for receiving the sheets to be fed to the converting machine.

When sheets are to be inverted before being fed, an infeed conveyortransfers a vertical stack of sheets horizontally onto a pivotablymounted V-shaped shingling conveyor. The shingling conveyor includesfirst and second conveyor supports at an acute angle. The first conveyorsupport has a conveyor thereon which conveys the stack against thesecond conveyor support to precondition the stack for shingling. Theshingling conveyor is pivoted through an arc of about lO-l30. Suchpivotable movement places the second conveyor support in a dischargeposition inclined upwardly at which time a plurality of conveyorsthereon and operating at progressively increasing speeds shingle thesheets and transfer them to an outfeed conveyor. As a result of saidpreconditioning, the sheets are all leaning in the direction ofdischarge when the second conveyor support is at its discharge position.Speed of the outfeed conveyor is preferably the same as the dischargespeed from said second conveyor support.

Since the sheets are turned over and shingled by the shingling conveyor,the entire device may be shorter than comparable devices proposedheretofore. The shingling conveyor and outfeed conveyor may be mountedon wheels so that they may be moved from machine to machine.Alternatively, the wheels will permit the shingling and outfeedconveyors to be moved to an inoperative position so as to enable amultisection machine to be opened, etc.

The outfeed conveyor delivers the sheets to the hopper of a feed table.The hopper is provided with detection means for detecting the level ofsheets in the hopper. If the height of the stack of sheets in the hopperexceeds a predetermined level, a switch is tripped to temporarily stopoperation of the outfeed conveyor. When the sheet level in the hopperhas decreased sufficiently, another switch restarts the outfeedconveyor.

It is an object of the present invention to provide novel apparatus forshingling sheets such as paperboard blanks.

It is another object of the present invention to provide novel apparatusfor shingling sheets wherein the sheets are preconditioned for shinglingwhile on a pivotably mounted shingling conveyor.

It is another object of the present invention to provide novel apparatusfor turning over stacks of sheets and shingling the same in a mannerwhich is simple, inexpensive and reliable.

It is another object of the present invention to control the feed ofsheets to a hopper of a feed table as a function of the height of thestack of sheets in the hopper.

Other objects will appear hereinafter.

For the purpose of illustrating the invention, there is shown in thedrawings a form which is presently preferred; it being understood,however, that this invention is not limited to the precise arrangementsand instrumentalities shown.

FIG. 1 is a side elevation view of apparatus in accordance with thepresent invention.

FIG. 2 is a plan view taken along the line 2-2 in FIG. 1.

FIG. 3 is an end view taken along the line 3-3 in FIG. 1.

FIG. 4 is a sectional view taken along the line 4-4 in FIG. 1.

FIGS. 5-11 are diagrammatic illustrations of the movement of theshingling conveyor from the receiving position to the dischargeposition.

FIG. 12 is a diagrammatic elevation view of a feed table and itsrelation to the outfeed conveyor.

FIG. 13 is a partial perspective view of the central portion of thefirst conveyor support on the shingling conveyor.

Referring to the drawings, wherein like numerals indicate like elements,there is shown in FIG. 1 apparatus for conveying sheets in accordancewith the present invention designated as 10. The apparatus 10 includes aframe designated generally as 12 on wheels 14 so that it may be movedtoward and away from the feed table 15.

The frame 12 includes upper and lower beams 16 and 18 on one side of theframe and on the other side of the frame upper and lower beams 20 and 22are provided. Each of the upper beams is interconnected by horizontallydisposed transverse beams. The lower beams are similarly coupledtogether. Each of the upper beams is coupled to its lower beam struts24.

A truncated triangular plate 26 is rotatably supported on the upper beam16 by means of shaft 30 and its bearing 32. A truncated triangular plate28 is rotatably supported on the upper beam 20 by means of a stub shaft34 and its bearing 36.

The plates 26 and 28 interconnect the converging conveyor supportsdesignated generally as 38 and 40. The first conveyor support 40receives a stack of sheets and the second conveyor support 38 dischargesthe stack of sheets in shingled form. The angular disposition of thesupports 38 and 40 is fixed and preferably is 45 but may be betweenabout 35 and The first and second conveyor supports constitute aV-shaped shingling conveyor 37 having its axis of pivotable movement atthe axis of the aligned stub shafts 30 and 34. Said axis is located atapproximately the center of gravity of the shingling conveyor 37.

The shingling conveyor 37 is adapted to pivot from the dischargeposition as shown in FIGS. 1 and 11 to the receiving position as shownin FIG. 5. Any one of a wide variety of devices may be utilized to pivotthe shingling conveyor 37. In the illustrated embodiment, such pivotablemovement through an arc of about lO0-l 30 is attained by means of firstand second cylinders 42 and 48. Cylinder 42 has one end pivotablyconnected to pin 44 on the frame 12 and has its piston rod pivotablyconnected to pin 46 on the second conveyor support 38. The cylinder 48is similarly positioned but on the opposite side of the frame as shownmore clearly in FIG. 2. If desired, a single large cylinder centrallydisposed may be utilized instead of the cylinders 42 and 48.

Referring to FIG. 2, the discharge end of the second conveyor support 38is approximately in the center of the figure. At the discharge end ofthe conveyor support 38, there is provided a pair of parallel shafts 50and 52 having reduced diameter end portions rotatably supported bybearings on the support 38. Endless belts 54, 56 and 58 are spaced fromone another and extend around the shafts 50 and 52.

The belt 54 is provided with a tension roller 60. See FIG. 4. Threadedbolts 62 and 64 are adapted to move the housing 66 for the roller 60upwardly or downwardly to adjust the tension of the belt 54. A similaradjustable tension roller 60' is provided for belt 56 and a similaradjustable tension roller 60" is provided for belt 58. Each of saidtension rollers is aligned with one another as shown more clearly inFIG. 2.

The remainder of the second conveyor support 38 is defined by a pair ofparallel shafts 68 and 86 having reduced diameter end portions rotatablysupported by bearings thereon. Parallel endless belts 72, 74 and 76extend around the shafts 68 and 86. Belt 72 is provided with a tensionroller 94, belt 74 is provided with a tension roller 95, and belt 76 isprovided with a tension roller 97.

As shown more clearly at the bottom of FIG. 2, shafts 68 and 52 areinterconnected by sprockets 80 of different sizes and chain 82 so thatbelts S4, 56 and 58 will move at a faster speed than the speed of belts72, 74 and 76. For example, if belts 72, 74 and 76 move at a speed ofabout 60 feet per minute, the belts 54, 56 and 58 will move at a speedof about 100 feet per minute. Motor 100 is coupled to shaft 50.Preferably motors 100, 132 and 163 are hydraulic motors coupled directto the belt drive shaft. Electric motors coupled through speed reducerscould also be used.

As shown more clearly in FIGS. 1 and 2, flat sheets are discharged frombelts 54-58 to a horizontal outfeed conveyor at section 104. Section 104has horizontal beams 106 and 108 on opposite sides of the frame 12supported by upright struts 114 extending to transverse beams 110 and112.

Section 104 includes parallel idler shaft 118 and drive shaft 116 havingtheir ends rotatably supported by bearings. Parallel belts 120, 122 and124 extend around the shafts 116 and 118. Belt 120 is provided withadjustable tension rollers 126 and 126'. Roller 126 is adjustable bymeans of threaded bolt 128 while roller 126' is adjusted by means ofbolt 128'. The belts 122 and 124 are provided with similar tensionrollers. Motor 132 is connected to drive shaft 116.

Belt 120 is provided with an idler roller 130. Belts 122 and 124 areprovided with a similar idler roller. Each of the belts 120-124 isdriven by drive shaft 116 at a speed which is preferably the same as thespeed of the belts 54-58.

The first conveyor support 40, as shown more clearly in FIG. 3, includesa pair of parallel shafts 134 and 136 having reduced diameter endportions supported by bearings. Parallel belts 138 and 142 extend aroundthe shafts 134 and 136. Shaft 134 is driven by motor 163.

As shown more clearly in FIG. 1, belt 138 extends over idler rollers 144and 146. Between the rollers 144 and 146, there is provided anadjustable tension roller 148. Tension is applied by means of thethreaded bolt 150. The belt 142 is similarly provided with tensionrollers and idler rollers.

A limit switch 160 is coupled to a solenoid control valve controllingflow to cylinders 42 and 48 whereby the shingling conveyor 37 assumesthe receiving position shown in FIG. 5. Switch 160 is connected also toa solenoid control valve for motor 163 which drives belts 138 and 142. Apendulum 162 having wheels 164 is pivotably connected to the firstconveyor support 40 and lies in a channel 166 between the conveyor belts138, 142. See FIG. 13. A limit switch 168 is located in channel 166 andprojects up to a position for contact with a stack.

The switch 168 is connected to the solenoid control valve for cylinders42 and 48 and causes a hydraulic fluid from tank 170 to flow into thecylinders to cause the piston rods to retract whereby the shinglingconveyor 37 will pivot from the receiving position shown in FIG. 5 tothe discharge position shown in FIG. 11. A backstop 172 prevents anysheets of the stack from entering the gap between the conveyor supports38 and 40.

A limit switch 174 is tripped by the shingling conveyor 37 when thelatter is in the discharge position shown in FIGS. 1 and 11. Switch 174is connected to the solenoid control valve associated with cylinders 42and 48 whereby their piston rods stop the pivotal move ment of theshingling conveyor 37. Switch 174 also stops motor 163, starts motor100, and activates a photocell 176.

The photocell 176 is mounted on one side of the frame 12 and a reflector178 is mounted on the other side of the frame 12. Cell 176 and reflector178 are positioned at the gap between the discharge end of the secondconveyor support 38 and the inlet end of section 104.

As shown more clearly in FIG. 12, the shingled sheets are fed into thehopper 180 of the feed table 15. Feed table 15 is preferably a vacuumfeed table as shown in U.S. Pat. No. 3,7l5,1l5 the disclosure of whichis incorporated herein. The bottom sheet to be fed under the front gate182 to the feed rolls 184 of the convert ing machine is held flat onrails 185 and fed from the bottom of the hopper 180 by a reciprocatingfeed plate 186.

The front gate 182 supports limit switches 188, and 192 at variousheights above the plane of rails 185. If there are insufficient sheetsin hopper 180 to trip switch 188, the fingers 194 (which correspond totabls 108 in said U.S. Pat. No. 3,7l5,l l5) lift up the trailing edgesof the sheets whereby no sheets are fed by the reciprocating feed plate186. If hopper 180 contains enough sheets to trip switch 192, motor 132of section 104 and motor 100 of section 38 stop. When the level of thesheets has decreased whereby switch 190 is released, motors 100 and 132start again.

The operation of the apparatus 10 is as follows:

The shingling conveyor 37 is pivoted by cylinders 42 and 48 until switch160 is tripped. The fluid flow to the cylinders is now stopped andconveyor 37 assumes the receiving position shown in FIG. 5 wherein thefirst conveyor support 40 is horizontally disposed. Switch 160 alsostarts motor 163. In this receiving position, a stack of sheets T suchas paperboard blanks is fed by an infeed conveyor onto the firstconveyor support 40. Belts 138 and 142, which are driven by motor 163,move the stack T toward and into contact with the backstop 172 and thesecond conveyor support 38. When switch 168 is tripped by the stack T,the cylinders 42 and 48 pivot the shingling conveyor 37 in acounterclockwise direction from the position shown in FIG. 5. When theshingling conveyor 37 assumes the position shown in FIG. 7, the entirestack T is supported by the first support 40 and backstop 172. Theshingling conveyor 37 continues to pivot as shown in FIGS. 7-11.

As shown in FIG. 10, the sheets of the stack T are preconditioned tolean in the direction of .discharge. Wheels 164 pivot with pendulum 162and make sure none of the sheets remain upright. When the shinglingconveyor 37 is in the position shown" in FIGS. l'and ll, switch 174 istripped. Switch 174 stops motor 163, starts motor 100, and stops theshingling conveyor 37 from pivoting. The sheets are shingled anddischarged to section 104.

The motor 163 for operating the belts 138 and 142' is operative as theshingling conveyor 37 pivots from the position shown in FIG. 5 to theposition shown in FIG. 11. The motor 100 is inoperative until theshingling conveyor 37 assumes the discharge position shown in FIG. 11.The respective motors 100 and 163 on the shingling conveyor 37 may beoperated, if desired, by switches responsive to the rotative position ofthe stub shafts 30 or 34. The progressive speeds of the sets of belts onthe second conveyor support 38 increase the degree of shingling andcreate a uniformly shingled pile that can be more easily controlled forfeeding onto the conveyor belts of section 104 and for transfer intohopper 180. While on section 104 or while in the hopper 180, theshingled paperboard blanks may be maintained in a straight pile by meansof spankers, not shown, and per se known to those skilled in the art.

When the entire stack T has left the shingling conveyor 37, the cell 176receives reflected light from reflector 178. This generates a signalwhich is used to operate cylinders 42 and 48 to recycle the shinglingconveyor 37 from the discharge position shown in FIGS. 1 and 11 to thereceiving position shown in FIG. 5. In view of the above description ofthe feed table 15 and the detailed description thereof in said patent, afurther description of its operation is not deemed necessary.

The present invention may be embodied in other specific forms withoutdeparting from the spirit or essential attributes thereof and,accordingly, reference should be made to the appended claims, ratherthan to the foregoing specification as indicating the scope of theinvention.

I claim:

1. Apparatus for shingling sheets from a stack comprising a frame,

a V-shaped shingling conveyor rotatably supported by said frame,

said shingling conveyor having first and second conveyor supportsdisposed at an acute angle to each other,

said first conveyor support having a conveyor thereon for moving a stackof sheets toward the plane of said second conveyor,

said second conveyor support having a conveyor thereon for moving sheetsaway from the plane of said first conveyor support,

motor means for driving said conveyors, and

means for pivoting said shingling conveyor about a transverse horizontalaxis from a stack receiving position to a discharging position whereinsheets from the stack lean in the direction of discharge on said secondconveyor support and are consecutively discharged in shingledrelationship.

2. Apparatus in accordance with claim I wherein the acute angle definedby the first and second conveyor supports is about 3570", and said firstand second conveyor supports being of approximately the same length.

3. Apparatus in accordance with claim 1 wherein said second conveyorsupport is angled upwardly in the discharge positionof said shinglingconveyor, and said second conveyor support having at least two conveyorsoperable at progressively increasing speeds.

4. Apparatus in accordance with claim 1 wherein said frame is mounted onwheels, said frame supporting an output conveyor section for receivingshingled sheets from the second conveyor support.

5. Apparatus in accordance with claim 1 wherein said means for pivotingthe shingling conveyor includes at least one power cylinder having oneend pivotably connected to the frame.

6. Apparatus in accordance with claim I wherein said second conveyorsupport includes a plurality of sets of conveyors, and means on saidsecond conveyor support for driving each of said sets of conveyors atprogressively increasing speeds with the conveyor of the slowest speedbeing immediately adjacent to said first conveyor support.

7. Apparatus in accordance with claim 6 including an output conveyor forreceiving sheets from said second conveyor support, and a hopper forreceiving sheets from said output conveyor, motor means for said outputconveyor being responsive to the level of sheets in said hopper in amanner so that the motor means stops the output conveyor if the level inthe hopper is above a predetermined level.

8. Apparatus in accordance with claim 1 wherein said first conveyorsupport and said second conveyor support are approximately the samelength and said axis being approximately at the center of gravity ofsaid conveyor supports.

9. Apparatus in accordance with claim 1 including a pendulum pivotablysupported by said first conveyor support for contacting sheets to applya biasing force on the sheets when the second conveyor support is in itsdischarge position.

10. Apparatus in accordance with claim 9 including a rotatable member onthe end of the pendulum remote from the location at which the pendulumis pivotably supported by the first conveyor support.

11. Apparatus in accordance with claim 1 including switch means forautomatically starting the conveyor on the first conveyor support whenthe latter is in a stack receiving position, and switch means forautomatically starting the conveyor on the second conveyor support whenthe latter is in its discharge position, the conveyor on said secondconveyor support being inoperative except when in its dischargeposition.

12. Apparatus in accordance with claim 1 wherein said shingling conveyoris pivotable through an arc of about -l30 from the stack receivingposition to the discharging position.

13. Apparatus comprising a feed table for feeding sheets, said tablehaving a hopper, means for feeding sheets one at a time from the bottomof the hopper, conveyor means for feeding sheets into the hopper, levelcontrol means for said hopper including means for disabling said feedingmeans until a predetermined number of sheets are in the hopper and meansfor disabling said conveyor means when the number of sheets in saidhopper is greater than a predetennined number of sheets, said conveyormeans including an outfeed conveyor, a shingling conveyor for deliveringshingled sheets to said outfeed conveyor, said shingling conveyorincluding first and second conveyor supports inconveyor, and meansassociated with the conveyor on said second conveyor support for movingthe sheets therealong at progressively faster speeds toward said outfeedconveyor.

i i i I l

1. Apparatus for shingling sheets from a stack comprising a frame, aV-shaped shingling conveyor rotatably supported by said frame, saidshingling conveyor having first and second conveyor supports disposed atan acute angle to each other, said first conveyor support having aconveyor thereon for moving a stack of sheets toward the plane of saidsecond conveyor, said second conveyor support having a conveyor thereonfor moving sheets away from the plane of said first conveyor support,motor means for driving said conveyors, and means for pivoting saidshingling conveyor about a transverse horizontal axis from a stackreceiving position to a discharging position wherein sheets from thestack lean in the direction of discharge on said second conveyor supportand are consecutively discharged in shingled relationship.
 2. Apparatusin accordance with claim 1 wherein the acute angle defined by the firstand second conveyor supports is about 35*-70*, and said first and secondconveyor supports being of approximately the same length.
 3. Apparatusin accordance with claim 1 wherein said second conveyor support isangled upwardly in the discharge position of said shingling conveyor,and said second conveyor support having at least two conveyors operableat progressively increasing speeds.
 4. Apparatus in accordance withclaim 1 wherein said frame is mounted on wheels, said frame supportingan output conveyor section for receiving shingled sheets from the secondconveyor support.
 5. Apparatus in accordance with claim 1 wherein saidmeans for pivoting the shingling conveyor includes at least one powercylinder having one end pivotably connected to the frame.
 6. Apparatusin accordance with claim 1 wherein said second conveyor support includesa plurality of sets of conveyors, and means on said second conveyorsupport for driving each of said sets of conveyors at progressivelyincreasing speeds with the conveyor of the slowest speed beingimmediately adjacent to said first conveyor support.
 7. Apparatus inaccordance with claim 6 including an output conveyor for receivingsheets from said second conveyor support, and a hopper for receivingsheets from said output conveyor, motor means for said output conveyorbeing responsive to the level of sheets in said hopper in a manner sothat the motor means stops the output conveyor if the level in thehopper is above a predetermined level.
 8. Apparatus in accordance withclaim 1 wherein said first conveyor support and said second conveyorsupport are approximately the same length and said axis beingapproximately at the center of gravity of said conveyor supports. 9.Apparatus in accordance with claim 1 including a pendulum pivotablysupported by said first conveyor support for contacting sheets to applya biasing force on the sheets when the second conveyor support is in itsdischarge position.
 10. Apparatus in accordance with claim 9 including arotatable member on the end of the pendulum remote from the loCation atwhich the pendulum is pivotably supported by the first conveyor support.11. Apparatus in accordance with claim 1 including switch means forautomatically starting the conveyor on the first conveyor support whenthe latter is in a stack receiving position, and switch means forautomatically starting the conveyor on the second conveyor support whenthe latter is in its discharge position, the conveyor on said secondconveyor support being inoperative except when in its dischargeposition.
 12. Apparatus in accordance with claim 1 wherein saidshingling conveyor is pivotable through an arc of about 100*-130* fromthe stack receiving position to the discharging position.
 13. Apparatuscomprising a feed table for feeding sheets, said table having a hopper,means for feeding sheets one at a time from the bottom of the hopper,conveyor means for feeding sheets into the hopper, level control meansfor said hopper including means for disabling said feeding means until apredetermined number of sheets are in the hopper and means for disablingsaid conveyor means when the number of sheets in said hopper is greaterthan a predetermined number of sheets, said conveyor means including anoutfeed conveyor, a shingling conveyor for delivering shingled sheets tosaid outfeed conveyor, said shingling conveyor including first andsecond conveyor supports inclined with respect to each other at a fixedangle and pivotable about a transverse horizontal axis, and eachconveyor support having conveyors thereon, said second conveyor supportbeing inclined upwardly toward said outfeed conveyor in the dischargeposition of the shingling conveyor for feeding sheets to said outfeedconveyor, and means associated with the conveyor on said second conveyorsupport for moving the sheets therealong at progressively faster speedstoward said outfeed conveyor.